NotePadLock ($2) is a secure note storage application that almost falls into an entirely different category from the other apps we’ve looked at, but is included here as it is a general-purpose secure storage app. Rather than taking the approach of a single password that opens up the entire database, NotePadLock uses a six-digit code as its filing system. You basically create a note with a title and text, and then lock it down with a six-digit code. You then use that particular code to retrieve or edit that particular note. If you want to create another note, you simply secure it with a different code.

You can re-save an existing note with the same code by tapping on the padlock, or change the code by tapping on a key icon that appears after editing an existing note. No master database or index of notes is provided. If you create a note with a given code and then forget that code, you will basically forget that this note even existed. This approach may appeal to a certain type of user, but in general it does not seem practical. Further, no encryption is supported at all, with all codes and notes being easily readable from your iPhone backup folder, which for the same reasons as described above for other applications leaves this particular app with our lowest rating. iLounge Rating: F.

Editors' Note: iLounge only reviews products in "final" form, but many companies now change their offerings - sometimes several times - after our reviews have been published.
This iLounge article provides more information on this practice, known as revving.